Plumbing – Water leaking when we are away for a few days

leakplumbing

our water system at home works perfectly when we are at home, but when we leave for more than a couple of days the bathroom starts leaking water that goes dripping right on the kitchen that is downstairs.

If we close the mains valve when we leave for few days the drip obviously doesn't occur.

Above the spot where we get the drip there's both the WC and the bathtub, both work fine when we are at home, but as soon as we don't use the water system for a few days, the leak comes back. (it's also quite a big leak, with many drops per minute)

The pipes have been assembled by the previous owner of the house, and he wasn't an expert. He used copper pipes, with plastic connectors similar to this: http://www.diy.com/departments/jg-speedfit-plastic-elbow-dia15-mm/34372_BQ.prd

Someone suggested me that it could be that the connectors are not sufficient for the pressure that we get from the mains, and the pressure gradually increases if we don't open the faucets when we are away, so eventually one of the connectors will start leaking.

Others say that the pressure from the mains is constant and this is not the case, but are actually unable to offer an alternative explanation.

Does anyone have any experience with similar problems?

Thanks,

Best Answer

(Not going to be as helpful as I'd hoped, but maybe helps you think of something you hadn't thought of)

Since you mentioned the kitchen is right below, I'm going to assume finished walls/ceilings and that you can't easily trace the pipes(or maybe you're lucky and it's a drop-tile ceiling?).

I've heard of a few ways to find a leak, but they almost all involve being able to reach the pipes - either to spray something like dish soap on them and watch for bubbles or put an improvised stethoscope(flat-head screwdriver, usually) to them so you can listen for the leak.

I've had both tub/toilet gasket go and not be obvious for a few days (wood subfloor wicked the water to about 4ft away in both cases), so that might be something to consider too.

Either way, there's a pretty good list of steps to try here: https://www.plumbingsupply.com/how-to-check-for-leaks.html Most of it depends on having access to the piping though.

Having said that, unless the local plumber has a camera s/he can fit down the copper pipe (?), they're going to have to make holes too...